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Flashcards in Spring 9 Deck (31):
1

Here is a vector:
(x)
(y)
What does x and y represent?

x = right
y = up

2

Here is a vector:
(-a)
(-b)
What does a and b represent?

a = left
b = down

3

Here is a vector:
(f)
(-g)
What does f and g represent?

f = right
g = down

4

Define congruent

Shape: Same size and shape
Angles: Same measure (degrees)
Sides: Same length

5

Define similar

Two figures that have the same shape. Ratios of lengths or angles are equal (e.g. enlargement).

6

What are the three important things to remember about bearings?

1) Measured from north.
2) In a clockwise direction.
3) Written as three figures.

7

Complete the sentence:
The mean is always...

...between the lowest and highest numbers.

8

What does Σ mean?

Sigma, meaning "sum of".

9

What does ∅ mean?

"Empty set"

10

What does A ∩ B mean?

A intersect B (both A and B)

11

What does A ∪ B mean?

A union B (A, B or both)

12

What does A' mean?

Not A

13

What does A ∪ B ∩(A ∩ B)' mean?

A union B but not A intersect B

14

What does ∩ mean?

But/And

15

Define positive correlation

As one quantity increases so does the other.

16

Define negative correlation.

As one quantity increases, the other decreases.

17

Define no correlation.

Both quantities vary with no clear relationship.

18

What should you do when asked to estimate values of one variable in comparison to the other on a graph?

Draw the line of best fit.

19

On scatter graphs, how can we describe the relationship between the data?

We can describe the relationship as:
A positive correlation
A negative correlation
No correlation

20

The line of best fit...

Shows the general trend of two points.
Must be straight
Does not have to go through the origin or any of the points

21

Frequency polygons are...

Plotted at the midpoint
Drawn with straight lines

22

What do you need to help you find out the average in a set of grouped data?

Data
Frequency (f) and total
Midpoint (mp)
Midpoint * Frequency (mp*f) and total

23

How do you find the maximum range with a set of grouped data?

Highest Nº in data - Lowest Nº in data = range
(Data table)

24

How do you find the modal group with grouped data?

Look at which group has the highest frequency (frequency table).

25

How do you find the mean estimate in a set of grouped data?

mp*f total / f total = mean estimate
(mp*f table, frequency table)

26

How do you find the median in a set of grouped data?

f total / 2 = x
Add frequencies up until you reach x
(frequency table)

27

On a map with a scale of 1:3,000,000 the distance between Edinburgh and London is 18cm. What is the actual distance, in kilometres, between these cities?

18cm*3,000,000cm = 54,000,000cm
100cm = 1m
54,000,000/100 = 540,000m
1000m = 1km
540,000/1000 = 540km

28

The actual distance between two places in 2.4km. If a map has a scale of 1:40,000 what distance on the map is used to represent it?

2.4km = 2400m
2400m = 240,000cm
240,000/40,000 = 6cm

29

Point B is 100m away from point A. The map uses a scale of 1:1000. What distance is shown on the map to represent this?

100cm = 1m
100cm*100 = 10,000cm
10,000cm/1000 = 10cm

30

Rewrite the interval 11-20 using inequalities.

10.5 < x ≤ 20.5

31

Rewrite the interval 31-40 using inequalities.

30.5 < x ≤ 40.5